#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=1e3+100;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
vector<LL>g[maxn];
struct Edge{
    LL u,v;
}edges[maxn];
map<LL,LL>map1;
LL ask(LL u,LL v){
   cout<<"? "<<u<<" "<<v<<endl;
   LL num;cin>>num;
   return num;
}
void pri(LL u){
   cout<<"! "<<u<<endl;
}
int main(void){
   LL n;cin>>n;
   for(LL i=1;i<n;i++){
       cin>>edges[i].u>>edges[i].v;
   }
   if(n==2){
      LL ans=ask(1,2);
      pri(ans);
      return 0;
   }
   if(n%2==0){
      LL tot=1;
      for(LL i=1;i<=n/2;i++){
          LL ans=ask(tot,tot+1);
          map1[ans]++;
          tot+=2;
      }
      for(auto i:map1){
         if(i.second>=2){
            pri(i.first);
            break;
         }
      }
   }
   else if(n&1){
      LL tot=1;
      for(LL i=1;i<n/2;i++){
          LL ans=ask(tot,tot+1);
          map1[ans]++;
          tot+=2;
      }
      map<LL,LL>::iterator it;
      it=map1.begin();
      LL num1=((*it).first);
      it=map1.end();
      it--;
      LL num2=((*it).first);
      LL ans=ask(num1,num2);
      map1[ans]++;
      for(auto i:map1){
         if(i.second>=2){
            pri(i.first);
            break;
         }
      }
   }
   return 0;
}
